[FFmpeg-devel] h264 - Correct implicit weight table computation for long ref pics

[Jeff Downs]

Correct computation of implicit weight tables when referencing pictures
that are marked for long reference.
---
 libavcodec/h264.c |    4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)

diff --git a/libavcodec/h264.c b/libavcodec/h264.c
index 5b5895c..ac8aa35 100644
--- a/libavcodec/h264.c
+++ b/libavcodec/h264.c
@@ -2206,9 +2206,10 @@ static void implicit_weight_table(H264Context *h, int field){
     for(ref0=ref_start; ref0 < ref_count0; ref0++){
         int poc0 = h->ref_list[0][ref0].poc;
         for(ref1=ref_start; ref1 < ref_count1; ref1++){
+            int w= 32;
+            if (!h->ref_list[0][ref0].long_ref && !h->ref_list[1][ref1].long_ref){
             int poc1 = h->ref_list[1][ref1].poc;
             int td = av_clip(poc1 - poc0, -128, 127);
-            int w= 32;
             if(td){
                 int tb = av_clip(cur_poc - poc0, -128, 127);
                 int tx = (16384 + (FFABS(td) >> 1)) / td;
@@ -2216,6 +2217,7 @@ static void implicit_weight_table(H264Context *h, int field){
                 if(dist_scale_factor >= -64 && dist_scale_factor <= 128)
                     w = 64 - dist_scale_factor;
             }
+            }
             if(field<0){
                 h->implicit_weight[ref0][ref1][0]=
                 h->implicit_weight[ref0][ref1][1]= w;
-- 
1.7.3.4